A building management system (BMS) is an electronic network used to monitor and control a building’s electrical and mechanical services, including heating, ventilation and air conditioning (HVAC), and lighting. A BMS can incorporate wider building services such as security, access control, elevator and safety systems. Depending on specific application and configuration, a BMS may be known by other names including a building automation systems (BAS), building management and control system (BMCS), and a building energy management system (BEMS).

A BMS gives owners and operators automated precision to optimise the performance and energy efficiency of their buildings from a single, intuitive digital interface. Installing a modern BMS enables occupant comfort to be delivered consistently and for the lowest possible energy use, delivering savings, improved productivity and reduced greenhouse gas emissions.

A BMS can be procured as a complete, engineered package or implemented as a means to integrate existing systems. Modern BMS applications are based on open communications protocols and are web-enabled, allowing integration of systems from multiple system vendors.

BMS allows comprehensive control and optimisation of equipment cycles, and can be implemented with control algorithms focused on energy efficiency. The following energy saving strategies can be enabled:

• Accurate control of a wider range of comfort conditions, including seasonal temperature adjustments.
• Precise start-up and run times, eliminating excess usage.
• Economy cycle control including CO2 occupancy control.
• Removing all overlap between systems, especially heating and cooling equipment.
• Automatically adjusting for seasonal conditions, including variable plant sequence selection.
• Variable air pressure control and coolant temperature control.

To get the most out of a BMS, correct location and calibration of sensors is crucial. This ensures the BMS is responding to accurate readings at all times. While many modern sensors do not suffer accuracy drift over time, a baseline error of up to one degree can occur and must be offset appropriately. Even greater inaccuracies can occur due to sensors being placed at the wrong height or near heat sources.

The automated functionality of a BMS takes the pressure off building managers to constantly monitor data and manually intervene in HVAC settings. The time saved on monitoring and tuning can free facilities staff to implement physical improvements and maintenance.

The BMS single-user interface also saves time by bringing all relevant information and controls together in one place.  Interfaces can range from basic dashboards through to full graphic workstations, but should always be intuitive to use, making monitoring and analysis easy. A BMS can quickly translate real-time data into useful business information, assisting rapid decision-making.

A BMS can implement strategies to reduce maximum demand charges, which make up a sizeable portion of many business’ energy bills. A BMS can anticipate high building loads and allow appropriate adjustments in advance to avoid maximum demand threshold levels.

Using public weather forecasts, a web-enabled BMS can anticipate favourable or extreme weather conditions and adjust HVAC sequences to achieve the most efficient outcome. For example, if the BMS anticipates a hotter than normal day to come, it can automatically pre-cool the building in advance to take advantage of off-peak energy or more favourable weather conditions.